Extra EOT from NoBuffering mode in emacs

Compile the following program:

import System.IO

main = hSetBuffering stdin NoBuffering >> getLine >>= print

Then start emacs, run M-x shell, and start the above program. Paste the output of replicate 252 'x' as input and press return. An extra EOT character is added to the end of the input:

$ ./foo
"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"     

"\"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\"\\
EOT"

I can make this happen consistently using Ubuntu 8.04.2 and emacs-22.1.1. I can't reproduce it on OS X or outside of emacs's shell.

This was originally reported on the Haskeline bug tracker, as it affects ghci/haskeline: http://trac.haskell.org/haskeline/ticket/79 . From that ticket:

The problem seems to be that Emacs does not send all of the input at once: If STRING is more than 500 characters long, it is sent in several bunches. This may happen even for shorter strings. (From the documentation of process-send-string in GNU Emacs 23.0.93.1.) See also the following message: http://thread.gmane.org/gmane.comp.lang.haskell.glasgow.user/15591/focus=15632.

Trac metadata

Trac field	Value
Version	6.10.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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